* {
    margin: 0;
    padding: 0;
    list-style: none;
}

.page {
    width: 500px;
    height: 40px;
}

.page button {
    float: left;
    margin-left: 5px;
    width: 80px;
    height: 40px;
}

.page .content {
    float: left;
}

.page .content .item {
    float: left;
    width: 40px;
    height: 40px;
    text-align: center;
    line-height: 40px;
    margin-left: 5px;
    background-color: black;
    color: burlywood;
}

.page .content .active {
    color: red;
}